The term “transparent pane” denotes here window and door elements as well as facade elements, separating walls, roof elements, anti-noise elements and such transparent, pane-like, flat or curved elements based on single-pane safety glass (ESG) or partially prestressed glass (TVG) or thermally treated glass (TBG) or composite safety glass (VSG) or insulating glass.
The term “bird strike” denotes the impact of a bird against such a pane, whereby the bird can be injured, which should be avoided by the protective device of the invention, and even the pane element can suffer damage by the force of the impact.
In order to avoid bird strikes, elements that are clearly visible to the human eye are customarily mounted on such pane-like glass fronts. In order to avoid pane damage, safety glass constructions or composite glass constructions or pane constructions with worked-in fibers or with grid-like elements are frequently used. Often, such fibers or grid-like elements are designed to be visually seen so that in addition to the strength even a visual warning is given.
EP 1 110 450 B1 cites an anti-bird device for a transparent substance which device has a greater absorption capacity and/or reflection capacity in a wavelength range that borders on the wavelength range visible for humans than in the visible range. Alternatively, the polarization of the light is altered.
DE 20215573 U1 and EP 1 319 335 B1 cite an anti-bird device for a transparent substance that has a main dimension (H) of less than 0.5 mm as an optically effective structure. This yields an undesired visibility for the human eye.
WO 2004 070 148 A2 cites an anti-bird device with a glass pane or plastic pane onto which or into which a screen that can be perceived by birds is worked in whose dimensions are in the μm range so that a pane transparency desired to a great extent for the human eye remains preserved.
The screen is preferably printed onto the pane on one side and has a punctual structure or a grid structure. The diameter of the points of the punctual screen is in the range of 10 to 100 μm, preferably 50 μm, whereby in the grid screen the line width is approximately 10 to 100 μm, preferably approximately 5 μm, and the mesh width is approximately 100 to 500 μm, preferably approximately 300 μm. The anti-bird screen is preferably colored black. However, this arrangement has the disadvantage that the slight contrast between the transparent range of the pane and the screen structure that is given for the eye of the birds results in an increased danger of impact.
The invention therefore has the basic task of improving the contrast effect of the anti-bird device for the bird's eye, whereby the transparency should be largely retained for the human eye.